I just added a custom configuration section in Thinktecture IdentityModel that will automatically drive the various SAM and FAM helper functions I added a while ago. The configuration looks something like this:

<configuration>
  <configSections>
    <section name="securitySessionConfiguration" 
             type="Thinktecture.IdentityModel.Web.Configuration.SecuritySessionSection, Thinktecture.IdentityModel"/>
  </configSections>

  <securitySessionConfiguration
    sessionTokenCacheType="WebRP.EF.EFTokenCacheRepository, WebRP"
    useMackineKeyProtectionForSessionTokens="true"
    defaultSessionDuration="01:00:00"
    persistentSessionDuration="01:00:00:00"
    cacheSessionsOnServer="true"
    enableSlidingSessionExpirations="true"
    overrideWSFedTokenLifetime="true"
    suppressLoginRedirectsForApiCalls="true"
    suppressSecurityTokenExceptions="true"
  />
</configuration>

With this in place you no longer need to explicitly invoke the various PassiveSessionConfiguration or PassiveModuleConfiguration APIs from global.asax. Also, each of these attributes is optional so you only need to specify the ones you care about.

HTH